Speak no evil. It starts with our mouths. So, if we let go our tongue then words coming out can be dangerous or good.
We have to learn self control to avoid saying the wrong things. Many times we do not use our bodies in a correct manner. So, we do need self control and process what we are about to say.
Every action comes with a consequence. As long as we know how to use every part of our bodies then we will be in good hands.